Add module param.c/param.h
- this allows support of parameter packs, which in particular enables
re-introducing of "format" and others in a more systematic manner
diff --git a/param.c b/param.c
new file mode 100644
index 0000000..7715571
--- /dev/null
+++ b/param.c
@@ -0,0 +1,140 @@
+/*
+ * This file is part of ltrace.
+ * Copyright (C) 2011,2012 Petr Machata, Red Hat Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#include <assert.h>
+#include <stdlib.h>
+
+#include "param.h"
+#include "type.h"
+#include "value.h"
+#include "expr.h"
+
+void
+param_init_type(struct param *param, struct arg_type_info *type, int own)
+{
+ param->flavor = PARAM_FLAVOR_TYPE;
+ param->u.type.type = type;
+ param->u.type.own_type = own;
+}
+
+void
+param_init_stop(struct param *param)
+{
+ param->flavor = PARAM_FLAVOR_STOP;
+}
+
+void
+param_init_pack(struct param *param,
+ struct expr_node *args, size_t nargs, int own_args,
+ struct param_enum *(*init)(struct value *cb_args,
+ size_t nargs,
+ struct value_dict *arguments),
+ int (*next)(struct param_enum *context,
+ struct arg_type_info *infop,
+ int *insert_stop),
+ enum param_status (*stop)(struct param_enum *ctx,
+ struct value *value),
+ void (*done)(struct param_enum *))
+{
+ param->flavor = PARAM_FLAVOR_PACK;
+ param->u.pack.args = args;
+ param->u.pack.nargs = nargs;
+ param->u.pack.own_args = own_args;
+ param->u.pack.init = init;
+ param->u.pack.next = next;
+ param->u.pack.stop = stop;
+ param->u.pack.done = done;
+}
+
+struct param_enum *
+param_pack_init(struct param *param, struct value_dict *fargs)
+{
+ struct value cb_args[param->u.pack.nargs];
+ size_t i;
+
+ /* For evaluation of argument expressions, we pass in this as
+ * a "current" value. */
+ struct arg_type_info *void_type = type_get_simple(ARGTYPE_VOID);
+ struct value void_val;
+ value_init_detached(&void_val, NULL, void_type, 0);
+
+ struct param_enum *ret = NULL;
+ for (i = 0; i < param->u.pack.nargs; ++i) {
+ if (expr_eval(¶m->u.pack.args[i], &void_val,
+ fargs, &cb_args[i]) < 0)
+ goto release;
+ }
+
+ ret = param->u.pack.init(cb_args, param->u.pack.nargs, fargs);
+
+release:
+ while (i-- > 0)
+ value_destroy(&cb_args[i]);
+ return ret;
+}
+
+int
+param_pack_next(struct param *param, struct param_enum *context,
+ struct arg_type_info *infop, int *insert_stop)
+{
+ return param->u.pack.next(context, infop, insert_stop);
+}
+
+enum param_status
+param_pack_stop(struct param *param,
+ struct param_enum *context, struct value *value)
+{
+ return param->u.pack.stop(context, value);
+}
+
+void
+param_pack_done(struct param *param, struct param_enum *context)
+{
+ return param->u.pack.done(context);
+}
+
+void
+param_destroy(struct param *param)
+{
+ if (param == NULL)
+ return;
+
+ switch (param->flavor) {
+ case PARAM_FLAVOR_TYPE:
+ if (param->u.type.own_type) {
+ type_destroy(param->u.type.type);
+ free(param->u.type.type);
+ }
+ return;
+
+ case PARAM_FLAVOR_PACK:
+ if (param->u.pack.own_args) {
+ size_t i;
+ for (i = 0; i < param->u.pack.nargs; ++i)
+ expr_destroy(¶m->u.pack.args[i]);
+ free(param->u.pack.args);
+ }
+ case PARAM_FLAVOR_STOP:
+ return;
+ }
+
+ assert(!"Unknown value of param flavor!");
+ abort();
+}